Electric thread cutting apparatus



Jan. 26, 1965 G. M. MARKS 3,167,097

ELECTRIC THREAD CUTTING APPARATUS Filed April 22, 1963 2 Sheets-Sheet l I INVENTOR. GEORGE M. MARKS FIG.3

Jan. 26, 1965 G. M. MARKS ELECTRIC THREAD CUTTING APPARATUS 2 Sheets-Sheet 2 Filed April 22, 1963 INVENTOR. GEORGE M. MARKS United States Patent This invention relates in general to textile machinery and more particularly to electric means for severing weft threads in a loom. The present invention comprehends improvements to the electric thread cutter described and claimed in applicants copending application, Serial Number 163,463, now US. Patent No. 3,135,298.

A principal object of the invention is the provision of an electric thread cutter for severing and coagulating the fibers in the weft threads in looms of the general Draper type.

i A further object of the invention is the provision of an adjustable spark gap means for attachment to the temple mechanism of the loom for automatically cutting weft threads in close proximity to the edge of cloth in a loom upon the depletion of the thread in each bobbin.

Another object of the invention is the provision of an automatic electric control means for energizing a thread cutting spark gap for a predetermined period when the severance of a weft thread in a loom is required.

Another object of the invention is the provision of electric time delay relay and circuit means for energizing a thread cutting spark gap for a predetermined period when initiated by the bobbin and shuttle transfer means in the loom is operated.

A further object of the invention is the provision of an electric spark gap attachment for -a loom temple ineluding adjustment means for positioning the gap in precise predetermined proximity with the edge of the cloth as woven.

These and other objects and advantages in one embodiment of the invention are described and shown in the following specification and drawing, in which:

FIG. 1 is a plan view in reduced scale of the temple portion of a loom with the spark gap positioned thereon in cutting relation to the edge of the woven cloth.

FIG. 2 is a side elevation of the apparatus shown FIG. 1.

FIG. 3 is a front elevation of the apparatus shown FIG. 1.

FIG. 4 is an enlarged cross sectional view taken through section line 4-4;, FIG. 1.

FIG. 5 is an enlarged perspective view of the spark gap elements shown FIG. 1.

FIG. 6 is a fragmentary perspective view of a loom control shaft and an electric control switch associated therewith.

FIG. 7 is a schematic diagram of the electric circuit for the thread cutting apparatus shown FIG. 1.

FIG. 8 is a perspective view of the loom control shaft shown FIG. 6 related to an alternate electric time delay control switch.

FIG. 9 is an alternate circuit for use with the delay switch shown FIG. 8.

Referring to FIG. 1 a temple assembly 1 is shown in working relation to the cloth 2 as woven in a loom. The edge 3 of the clothis caused to move in a straight line colinear with and in the direction shown by arrow. The weft thread 4 represents the end portion of the thread on each bobbin which requires cutting prior to the sequential insertion of each full bobbin in a shuttle.

Referring to FIGS. 1 and 2, bracket 5 made of metal is secured to the base 6 of the temple by means of a screw 7 through a lateral slot 3 threaded into engagement with base 6 of temple 1 shown FIG. 5.

Referring to FIGS. 1 through 5, the bracket 5 has a linear groove therein for locating a cylindrical ceramic insulator 9 which has an upper electrode 1d coaxially secured in and extending from one end thereof. A clamp it retained to bracket 5 by screw 12 adjustably secures insulator 9 on the groove on bracket in predetermined longitudinal and radial position. A high tension insulated conductor 13 is coaxially secured in the insulator 9 and is internally connected to electrode 10 by means not shown. The electrode 10 is formed into a double offset terminating in a spherical tip 14 as shown in FIG. 5. The

electrodes are preferably made of oxidation resistan.

metal, such as tungsten or stainless steel.

lower electrode 15 is adjustably secured in bracket 5 by set screw in, as shown, and includes a double olfset terminating in a tip 17 positioned substantially coaxial with and adjacent tip 14 as shown.

A thread guide 18 preferably made from insulating material, such as synthetic porcelain, is secured to electrode 15 by set screw 19 and is provided with a tapered slot 20, better shown in FIG. 4, for guiding a weft thread into the gap between electrode tips 14 and 117.

A schematic circuit diagram shown FIG. 7 includes a voltage reducing transformer 21, a holding relay 22, a time delay relay 23, a high tension ignition transformer 24 and a normally open control switch 25.

Qne side of a normal industrial alternating current power source L is connected to one terminal of the primary of transformer 21, one terminal of relay 23 and one terminal of the primary of transformer 24 by conductor 26. The remaining side of the source of power L is connected to the remaining primary terminal of transformer 21 and a normally open relay switch blade 27 by conductor 28. Relay switch blade 29 is connected to the remaining terminal of relay 23 and the remaining primary terminal of transformer 24 by conductor 30. Normally open relay switch blade 31 is connected to normally closed relay blade 32 by conductor 33.

Relay blade 34 is connected to one terminal of relay 22 and one terminal of switch 25 by conductor 35. A secondary terminal of transformer 21 is connected to the remaining terminal of relay 22 it by conductor 36. Normally closed blade 37 of relay 23 is connected to the re maining secondary terminal of transformer 21 and to the remaining terminal of switch 25 by conductor 38. The high tension secondary of transformer 24 is connected to the upper and lower spark gap electrodes 10 and 15 by conductor 13 and a common ground conductor 39 respectively.

It has been found that because of personnel and fire hazard the conductor 13 should be made as short as possible from a junction box containing the circuit elements and the conductors running to control switch 25 will operate at low tension provided by transformer 21.

It has also been found desirable to limit the period of spark discharge in the gap 43 to that required only to sever each weft thread, therefore the gap is energized only for a time period corresponding to the time delay relay 23, which is energized by circuit means when the switch shown FIG. 6 is momentarily closed during the sequential cyclic bobbin action of the loom corresponding to the oscillation of shaft it in operation the electrodes are adjusted to straddle the lateral path of movement of the weft threads by first adjusting the bracket 5 with respect to the temple base 6, to position the gap in predetermined proximity to the edge of the cloth. By frictionally positioning the insulator 9 by loosening screw 12 and simultaneously adjusting the electrode 15 by loosening screw 16 the gap between the tips 14 and 15 is adjusted to accurately straddle the path of the thread and is also proportioned to produce a desirable fat spark discharge, then the slot 20in the guide 18 is adjusted to center the thread in the l hen the loom is in operation and when a weft thread is advanced with the woven cloth toward the gap for severancetit'will'be guided and stabilized against vibrat-ion by the tapered slot 20 in the guide 18 since it is importantthat the thread does not physically contact either of the electrode tips 14 and 17 which must be free of char. At the time of sequential bobbin replacement in a loom one of several shafts in the loom mechanism are caused to oscillate and a particular shaft 4i is selected for operating a cam 41 and control switch When this shuttle cycle in the loom takes place the switch 25 is momentarily closed which will energize and operate relay 22' closing. both pair of its blades. Blades 31 and 34 will hold relay 22, energized by virtue of the closed blades 32 and 37 of the relay 23. The simultaneous closure of relay blades 27 and 29 will simultaneously energize the time delay relay 23 and the high tension transformer 24 to provide a spark discharge in the gap between electrodes 1t) and 15. The spark discharge will continue for a period of time determined by the adjustment of time delay relay 23,during which time the weft thread will be entered into the spark. gap between tips 14 and 17 and be severed thereby.

In the event the thread comprises synthetic fibers such as Dacron, Orlon, nylon, fiberglass or like fibers the ends of the fibers will be welded together and thus prevent unraveling of the thread.

The time period required for the spark discharge will vary from to seconds depending on the size of the character of the thread to be cut.

Following the predetermined time delay period of relay 23 the blades 32 and 37 will open and de-energize relay 22 whichin turn will de-energize transformer 24 and extinguishthe spark discharge and condition the circuit for recycling.

'FIG; 8 illustrates an alternate means for providing periodic energizing of the high tension transformer 24 by means of an electro-mechanical' time delay switch 42 which is connected in series with the power source L and L and the primary of the transformer 2 as shown in FIG. 9., The electro-mechanical switch 42 will operate satisfactorily but is considerably more expensive and requires more space and careful placement and adjustment in relation to a moving part in the loom as compared to circuit using the control switch and the circuit elements shown FIG. 7.

It is understood that certain modifications of the apparatus utilizing the features described are intended to come Within. the scope of the appended claims.

Having described my invention, I claim:

1, A thread cutter for severing weft threads projecting from cloth moving in a loom comprising a bracket member constructed and adapted to be adjustably secured to the temple assembly of a loom, an electric conductor carried by said bracket member, an insulator adjustably secured to said bracket member, an upper electrode member rigidly secured to said insulator with a portion of said upper electrode member extending from said insulator to a predetermined position above and in close proximity with the lateral path of travel of said weft threads, a lower electrode member adjustably secured to saidbracket member with a portion of said lower electrode member extending from said bracket member to below said upper electrode member and in a predetermined coaxial spaced relationship with respect to said upper electrode member below the path of travel of said weft threads, a thread guide interconnected to said bracket member including a slot lying in a substantially horizontal plane extending b tween said electrodes, said slot sequentially guiding said weft threads between said electrodes and spaced a relatively small distance from each of said electrodes, a source of electricity selectively producing an electrical spark between said electrodes, switch means included in said loom responsive to the advance of each of said weft threads towards said electrodes by producing a continuous electrical spark between said electrodes severing said thread, and a delay switch limiting the duration of said electrical spark a predetermined length of time sufficient to complete the severance of said thread.

2. A thread cutter in accordance with claim 1 wherein said insulator is cylindrical in shape with a substantially horizontally disposed longitudinal axis, and including a detachable clamp means securing said insulator to said bracket member, said upper electrode member including a portion fixed substantially horizontally in said insulator and extending from one end thereof.

3. A thread cutter in accordance with claim 2 wherein said upper electrode member'includes an offset portion extending substantially normally from said portion in said insulator.

References Cited by the Examiner UNITED STATES PATENTS 1,228,814 6/17 Owens 139266 2,481,048 9/49 Smith 19-.3 2,592,463 4/52 Phillips. 2,628,412 2/53 Vera. 2,928,431 3/60 Poole et al 139266 3,128,797 4/64 La Valley 139266 FOREIGN PATENTS 1,218,502 12/59 France.

481,584 6/53 Italy.

DONALD K. PARKER, Primary Examiner. 

1. A THREAD CUTTER FOR SEVERING WEFT THREADS PROJECTING FROM CLOTH MOVING IN A LOOM COMPRISING A BRACKET MEMBER CONSTRUCTED AND ADAPTED TO BE ADJUSTABLY SECURED TO THE TEMPLE ASSEMBLY OF A LOOM, AN ELECTRIC CONDUCTOR CARRIED BY SAID BRACKET MEMBER, AN INSULATOR ADJUSTABLY SECUREDD TO SAID BRACKET MEMBER, AN UPPER ELECTRODE MEMBER RIGIDLY SECURED TO SAID INSULATOR WITH A PORTION OF SAID UPPER ELECTRODE MEMBER EXTENDING FROM SAID INSULATOR TO A PREDETERMINED POSITION ABOVE AND IN CLOSE PROXIMITY WITH THE LATERAL PATH OF TRAVEL OF SAID WEFT THREADS, A LOWER ELECTRODE MEMBER ADJUSTABLY SECURED TO SAID BRACKET MEMBRE WITH A PORTION OF SAID LOWER ELECTRODE MEMBER EXTENDING FROM SAID BRACKET MEMBER TO BELOW SAID UPPER ELECTRODE MEMBER AND IN A PREDETERMINED COAXIAL MEMBER LATIONSHIP WITH RESPECT TO SAID UPPER ELECTRODE MEMBER BELOW THE PATH OF TRAVEL OF SAID WEFT THREADS, A THREAD 